NYPD forensic experts are examining the 9-mm bullet taken from the body of Akai Gurley, the Brooklyn man fatally shot by a police officer, in an effort to shed more light on what happened at the Pink Houses in East New York, a law enforcement official said. Photo Credit: Facebook

Brooklyn District Attorney Kenneth Thompson said Friday that a grand jury will be impaneled in the case of Akai Gurley, who was fatally shot by a rookie NYPD police officer in a dark public housing stairwell.

Mayor Bill de Blasio and Police Commissioner William Bratton have called the shooting a tragic accident, with Bratton saying Gurley was "a total innocent."

"I pledge to conduct a full and fair investigation and to give the grand jury all of the information necessary to do its job," he said in a statement.

Hours earlier, Gurley's family called for de Blasio and Thompson to investigate the case as a homicide. "My son didn't deserve to die like that," said Sylvia Palmer, Gurley's mother.

Thompson said there was no timetable for the grand jury to be impaneled. Grand juriesare normally convened for 30 days, but Thompson could ask the court to convene a special panel to hear only the Gurley matter as was done in the Eric Garner investigation.

Garner, 43, died in July after being placed in an apparent chokehold by an NYPD officer in Staten Island, but the grand jury Wednesday ruled out criminal charges.

Gurley, 28, was killed the morning of Nov. 20 when Officer Peter Liang shot him in the chest in a stairwell at the Louis H. Pink Houses in the East New York section of Brooklyn.

Police said the shooting appeared to be an accidental discharge.

Investigators said Liang held his drawn weapon in his left hand, which may have been jostled as he opened the stairwell door; and the single shot that killed Gurley may have ricocheted off a stairwell wall.

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"He was a very great person, and he leaves behind a 2-year-old daughter," she said. "We want justice for Akai . . . I want an indictment."

Palmer said her son, who lived in Brooklyn's Red Hook Houses, had been planning a Thanksgiving visit and she was looking forward to seeing her granddaughter for the first time.

"My son's heart was taken away so innocently. He did nothing wrong," she said. "Nothing in this world will heal my pain and heartache."

King Wayne, 31, of East New York, outside the church after the service, said, "It's sad that they put police officers in our neighborhoods that are afraid of us. . . . We're not ever safe in our own neighborhood, not even from them."

Thompson's staff is sorting through a still uncertain timeline of events.

A law enforcement official said Liang has yet to be interviewed but that his partner, who was with him in the stairwell, described how Liang jumped back when his gun discharged and exclaimed, "I accidentally fired my gun."

It remains unclear if Liang saw Gurley.

Liang and his partner later found the wounded man lying down on the fifth floor, with his girlfriend trying to revive him, the official said.

Immediately after the shooting, the girlfriend ran to a friend's fourth-floor apartment and told her to call police.

The first 911 call was recorded at 11:14 p.m., and about five minutes later, an NYPD lieutenant who was in the vicinity was at the scene, the official said.